Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "variants\\[([0-9]{6})\\]\\[1\\]\\[([0-9]{1,6})\\] \\= 237228\\;"; final String string = "var variants = [];\n" + "variants[208091] = [[80.00, 958, new Image(), '8.00', 80.00, \"LUG-CENTRIC-SPACERS\"],{},{},[]];\n" + "variants[208091][1][36366] = 237228;\n" + "variants[208092] = [[80.00, 941, new Image(), '8.00', 80.00, \"4112-5-55-L\"],{},{},[]];\n" + "variants[208092][1][36366] = 237229;\n" + "variants[208093] = [[80.00, 957, new Image(), '8.00', 80.00, \"4112-5-55-LM\"],{},{},[]];\n" + "variants[208093][1][36366] = 237230;\n" + "variants[208094] = [[80.00, 954, new Image(/r), '8.00', 80.00, \"4112-6-55-L\"],{},{},[]];\n" + "variants[208094][1][36366] = 237231;\n" + "variants[208095] = [[115.00, 948, new Image(1), '8.00', 115.00, \"4112-8-65-L\"],{},{},[]];\n" + "variants[208095][1][36366] = 237232;\n" + "variants[208096] = [[115.00, 958, new Image(69), '8.00', 115.00, \"4112-8-65-LM\"],{},{},[]];\n" + "variants[208096][1][36366] = 237233;\n" + "variants[216938] = [[80.00, 998, new Image(), '8.00', 80.00, \"4112-6-55-14-L\"],{},{},[]];\n" + "variants[216938][1][36366] = 244691;\n" + "variants[216939] = [[115.00, 1000, new Image(), '8.00', 115.00, \"4112-8-170-L\"],{},{},[]];\n" + "variants[216939][1][36366] = 244692;\n" + "variants[218025] = [[80.00, 998, new Image(), '8.00', 80.00, \"4112-5-45-L\"],{},{},[]];\n" + "variants[218025][1][36366] = 245809;\n" + "variants[228776] = [[115.00, 1000, new Image(), '8.00', 115.00, \"4112-8-180-L\"],{},{},[]];\n" + "variants[228776][1][36366] = 254512;\n" + "variants[228819] = [[80.00, 1000, new Image(), '8.00', 80.00, \"4112-5-150-L\"],{},{},[]];\n" + "variants[228819][1][36366] = 254558;\n"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html